A bilayer bioengineered patch with sequential dual-growth factor release to promote vascularization in bladder...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Bladder tissue engineering aims to repair defects but is limited by poor vascularization.
• Inadequate blood supply hinders engineered tissue survival and function post-transplantation.

Purpose of the Study:

• To develop a bilayer silk fibroin (BSF) scaffold for enhanced vascularization in bladder tissue engineering.
• To achieve sequential release of vascular endothelial growth factor (VEGF) and platelet derived growth factor-BB (PDGF-BB) for improved tissue regeneration.

Main Methods:

• Fabrication of a bilayer silk fibroin scaffold with distinct inner and outer layers.
• Incorporation of silk fibroin microspheres loaded with VEGF and PDGF-BB for controlled release.
• In vitro assessment of endothelial cell behavior and adipose-derived stem cell differentiation.
• In vivo transplantation of the BSF scaffold for bladder reconstruction evaluation.

Main Results:

• The BSF scaffold demonstrated controlled sequential release of VEGF and PDGF-BB.
• Scaffold exhibited excellent biocompatibility, promoting endothelial cell migration and differentiation.
• In vivo studies showed enhanced regeneration of urothelium, smooth muscle, and significant blood vessel formation.

Conclusions:

• The novel BSF scaffold effectively promotes vascularization in bladder reconstruction.
• This bioengineered patch offers a viable solution for future clinical applications in bladder repair.